JP5730073B2 - Turbine casing structure and method for removing internal members of turbine casing - Google Patents

Description

  The present invention relates to a turbine casing structure and a method of taking out an internal member of a turbine casing, and more particularly, to a turbine casing structure in which an inner casing is provided in an outer casing, and an inner casing in the casing structure. It is related with the internal member taking-out method.

  In general, a steam turbine is provided with an inner casing in an outer casing, a steam inlet portion at an upper portion, and a rotor rotatably supported at a central portion. A blade ring is supported in the inner casing, and a plurality of stages of stationary blades are provided on the blade ring, and a plurality of blades are fixed to the rotor. The stationary blades and the moving blades are alternately arranged.

  Usually, the external casing that constitutes such a steam turbine is configured to be divided into two upper and lower parts on a plane passing through the axis of the rotor in order to improve workability such as inserting, assembling, and disassembling the rotor. It is assembled with bolts.

  In recent years, it has been desired to increase the capacity of a steam turbine in order to improve the power generation capacity and power generation efficiency of a generator driven by the steam turbine. In order to increase the capacity of the steam turbine, it is necessary to lengthen the moving blade and the stationary blade, and in order to increase the length of the moving blade and the stationary blade, it is necessary to increase the size of the external casing.

By the way, when the upper compartment (hereinafter referred to as the upper compartment) is lifted by dividing the outer compartment into two parts at the top and bottom, such as during periodic inspections, to open the external compartment and move the upper compartment, It is necessary to lift the upper compartment to a height that exceeds the surrounding obstacles.
For this reason, when the outer casing is enlarged, the upper casing is also enlarged. Therefore, it is necessary to lift the upper casing to a position higher than the conventional level during the movement, and the ceiling height of the building where the steam turbine is installed is higher than before. You have to increase the height. Therefore, along with the increase in the size of the steam turbine, there is a possibility that the ceiling of the existing building may need to be raised depending on the height of the ceiling, and also when the building is newly constructed, the ceiling height of the building is increased. There is a problem that the construction cost of the building becomes high.

In view of this, it is conceivable that the external casing can be divided into four parts centered on the rotor instead of the upper and lower parts. A technique for enabling the external casing to be divided into four with the rotor as the center is disclosed in Patent Document 1, although the purpose is different.
However, even if the outer casing is configured to be divided into four parts centering on the rotor as disclosed in Patent Document 1, the height of the upper part of the outer casing is not different from that of the upper casing. The height does not change and the problem cannot be solved.

  Therefore, in Patent Document 2, the height of the upper compartment is lowered by setting the division position for dividing the external compartment into two upper and lower parts higher than the plane passing through the axis of the rotor. A technique capable of reducing the lifting height when lifting the hood is disclosed.

JP 2001-271606 A JP 2009-243413 A

  However, in the prior art disclosed in Patent Document 2, although it is possible to lower the lifting height of the upper casing, it is still necessary to lift the upper casing, and the size of the steam turbine is still increased. Depending on the degree of the vehicle and the size of the surrounding obstacles, it may be necessary to lift the upper compartment to a considerable height, and the ceiling of the building may need to be raised.

  Therefore, in view of the problems of the prior art, the present invention has a steam turbine casing structure in which the outer casing is configured to be divided into an upper casing and a lower casing in the vertical direction, and the upper casing is lifted without lifting the upper casing. An object of the present invention is to provide a turbine casing structure in which a casing can be separated from a lower casing and removed. It is another object of the present invention to provide a method for removing a member existing in the outer casing from a gap that can be removed by removing the upper casing of the outer casing.

  In order to solve the above-described problems, in the present invention, an internal casing in which a rotor is inserted and an external casing provided outside the internal casing are provided, and the external casing is arranged above and below. In the turbine casing structure configured to be split into a casing and a lower casing, the upper casing is configured to be split in two in the vertical direction, and each member that divides the upper casing into two is provided. A guide portion is provided for restricting sliding movement in a direction perpendicular to the axis of the rotor.

Thereby, it becomes possible to remove the upper compartment from the lower compartment without lifting the upper compartment. Therefore, there is no need for a crane or the like for lifting the upper compartment, and there is no need to change the ceiling height of the building where the turbine is installed as the turbine becomes larger.
Further, by providing the guide portion, it is possible to regulate the sliding direction of each member that divides the upper casing into two, and to move the member in a necessary direction with certainty.

In addition, the upper casing has a small-diameter position and a large-diameter position with different diameters around the rotor, and the cross-section in the direction orthogonal to the axis of the rotor is formed in a substantially semicircular shape. The position may include an axial position of the rotor in which the internal casing or the rotor is present.

  As a result, the members divided into two parts of the upper casing are slid, and when the internal members such as the inner casing and the rotor are taken out from the space formed by the sliding movement, they are taken out beyond the small diameter position. Thus, the lifting height of the internal member when the internal member is taken out can be kept low. Therefore, the labor saving of the machine which hangs an internal member is attained.

In addition, the upper casing and the lower casing are provided with flange portions facing each other,
The guide portion is composed of a groove in a direction orthogonal to the axial direction of the rotor provided on the opposing surface of one of the flange portions, and a protrusion that fits in the groove provided on the opposing surface of the other flange portion. It is good to be done.
Thereby, a guide part can be formed easily.
In addition, since the said flange part can utilize what is used as a fixing | fixed part when using it without dividing | segmenting an upper casing and a lower casing at the time of a driving | running | working of a turbine, etc., the said groove | channel and protrusion are provided in the existing flange. It is only necessary to provide it, and modification for carrying out the present invention is also easy.

  Further, it has an internal compartment in which a rotor is inserted and an external compartment provided outside the internal compartment, and the external compartment is configured to be vertically divided into an upper compartment and a lower compartment. In the turbine casing structure, the upper casing is configured to be divided in two in the vertical direction, and each member that divides the upper casing in two is in the same direction as the axial direction of the rotor. And it is supported by the said lower casing so that rotation is possible centering | focusing on the rotation center.

Thereby, it becomes possible to remove the upper compartment from the lower compartment without lifting the upper compartment. Therefore, there is no need for a crane or the like for lifting the upper compartment, and there is no need to change the ceiling height of the building where the turbine is installed as the turbine becomes larger.
Furthermore, by supporting each member that divides the upper casing in two so as to be rotatable around the rotation center, the movement direction of the member can be regulated and reliably moved in a necessary direction.

Further, the upper casing is formed of two semicircular end plates arranged opposite to each other in the axial direction of the rotor, and a side plate provided between the end plates. it may be constructed to be detachable part of the bottom near the center in the direction perpendicular to the axial direction of the rotor.
Thereby, by rotating each member divided into two parts of the upper casing, and removing the internal members such as the inner casing and the rotor from the space created by the rotational movement, the part is removed. When the internal member is taken out beyond the position where the part is removed, the lifting height of the internal member when the internal member is taken out can be kept low. Therefore, the labor saving of the machine which hangs an internal member is attained.

Further, as an invention relating to a method for taking out an internal member of a method for solving the problem, an internal compartment in which a rotor is inserted and an external compartment provided outside the internal compartment are provided. A guide part configured to divide the upper and lower chambers into an upper casing and a lower casing, and to restrict each member that divides the upper casing into two in a direction perpendicular to the axial direction of the rotor. A method of taking out an internal member of a turbine casing provided with a gas turbine, wherein after dividing the upper casing and the lower casing, the upper casing is divided into two in the vertical direction, and the upper casing is divided into two Each member is controlled to slide in the direction orthogonal to the axis of the rotor while the sliding direction is regulated by the guide portion , and the member in the external vehicle interior is taken out from the space formed by the sliding movement.

Further, the upper casing, together with cross-section is formed in a substantially semicircular shape in the direction perpendicular to the axis of the rotor, diameter centered on the rotor be one having a different diameter position and the large-diameter position respectively The member inside the external vehicle compartment may be hung over the upper portion of the small diameter position.

  Further, it has an internal compartment in which a rotor is inserted and an external compartment provided outside the internal compartment, and the external compartment is configured to be vertically divided into an upper compartment and a lower compartment. Each of the members obtained by dividing the upper casing and the lower casing into two parts in the vertical direction and dividing the upper casing into two parts. Is rotated about a rotation center that is in the same direction as the axial direction of the rotor and supported by the lower casing, and a member inside the outer casing is taken out of the space formed by the rotation. Features.

In addition, a part of the lower part of the two end plates that are provided so as to be opposed to the axial direction of the rotor and that constitute the external casing, respectively, near the center in the direction perpendicular to the axial direction of the rotor is removed. from each of the member divided into two parts the upper casing may be pivoted.

  According to the present invention, in the casing structure of the steam turbine configured so that the outer casing can be divided into the upper casing and the lower casing in the vertical direction, the upper casing is separated from the lower casing without lifting the upper casing. A turbine casing structure that can be divided and removed can be provided. Further, in the turbine casing structure of the turbine, it is possible to provide a method of removing a member existing in the outer casing from a gap that can be removed by removing the upper casing of the outer casing.

1 is a front view of a steam turbine according to Embodiment 1. FIG. 1 is a schematic front view of an upper casing of a steam turbine according to Embodiment 1 and its surroundings. FIG. 3 is a top view of the upper compartment according to the first embodiment. FIG. 3 is a side view of the upper compartment according to the first embodiment. FIG. 3 is a perspective view of an upper compartment in the first embodiment. It is a side view of the horizontal flange part used in order to couple | bond an upper compartment and a lower compartment in Example 1. FIG. It is the front schematic of the upper compartment after moving the upper compartment horizontally in Example 1, and its periphery. It is a front schematic diagram of the upper casing of a steam turbine concerning Example 2, and its peripheral thing. FIG. 6 is a perspective view of an upper compartment according to a second embodiment.

  Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention unless otherwise specified, but are merely illustrative examples. Not too much.

First, the outline of the structure of the steam turbine according to the first embodiment will be described with reference to FIG.
FIG. 1 is a front view of a steam turbine according to a first embodiment.
As shown in FIG. 1, the steam turbine 1 according to the present embodiment includes an internal casing 3 surrounding the rotor 2 and an external casing 4 provided outside the internal casing 3, and flows into the center of the casing. After the steam flows in the inner casing 3 in a branched manner, the steam enters the condenser (not shown) installed at the lower part of the steam turbine 1 from the exhaust holes (not shown) at both ends of the outer casing 4. It is configured.

  The outer casing 4 is divided into an upper half (upper casing 41) and a lower half (lower casing 42) on a horizontal plane passing through the rotor 2, and is bolted at the horizontal flange portions 4a and 4b. ing.

The upper casing 41 constituting the outer casing 4 is formed in a substantially bowl shape with an end plate 41a and a side plate 41b, and a plurality (five in FIG. 1) are provided on the outer surface of the end plate 41a. The I-shaped rib 41d is joined by welding or the like. The details of the shape of the upper compartment 41 will be described later.

  The steam turbine 1 is supported on a foundation 10 by a foot plate 8 with a cushioning material 6 as necessary. The foot plate 8 turns from the lower half side plate of the lower casing 42 to the end plate side and is directly joined to the outer surface of the end plate by welding or the like.

Next, the structure of the upper compartment according to the first embodiment will be described with reference to FIGS.
FIG. 2 is a schematic front view of the upper casing and its surroundings of the steam turbine according to the first embodiment. FIG. 3 is a top view of the upper compartment according to the first embodiment, and corresponds to a view in the direction of arrow A in FIG. FIG. 4 is a side view of the upper compartment according to the first embodiment, and corresponds to a view in the direction of arrow B in FIG. FIG. 5 is a perspective view of the upper compartment in the first embodiment.

The upper compartment 41 is formed in a substantially bowl shape having a recess 45 as shown in FIGS. 3 to 5 by two end plates 41a, three side plates 41b, and two middle plates 41c. .
In addition, the axial length l of the rotor 2 of the recess 45 is determined by the length of the internal casing accommodated in the external casing 4 and the axial length of the rotor 2. Is longer than the axial length of the inner casing and the rotor 2.

  Further, the upper compartment 41 is configured to be divided into two in the vertical direction. That is, the upper compartment 41 is configured by assembling the upper left compartment 43 and the upper right compartment 44 fixed by fixing means (not shown). The fixing means only needs to be fixed so that the upper left casing 43 and the upper right casing 44 are not divided when the steam turbine 1 is not required to be divided, for example, when the steam turbine 1 is operated. A bolt or the like can be used.

Next, the horizontal flange portions 4a and 4b used for connecting the upper casing 41 and the lower casing 42 will be described with reference to FIG.
FIG. 6 is a side view of a horizontal flange portion used for connecting the upper casing 41 and the lower casing 42, and corresponds to a view in the direction of arrow C in FIG.

As shown in FIG. 6, the horizontal flange portion 4a and the horizontal flange portion 4b are fixed by inserting a plurality of bolts 12 into the horizontal flange portion 4a and the horizontal flange portion 4b.
The horizontal flange portion 4a is provided with a groove portion 11a on the lower side in a direction perpendicular to the axial direction of the rotor 2, and the horizontal flange portion 4b is provided with a projection portion 11b on the upper side. The groove portion 11a and the projection portion 11b are configured to be fitted when the horizontal flange portions 4a and 4b are fixed. In this embodiment, the concave portion is provided below the horizontal flange portion 4a and the convex portion is provided above the horizontal flange portion 4b. Conversely, the convex portion is provided below the horizontal flange portion 4a, and the upper side of the horizontal flange portion 4b. It is also possible to provide a recess in
Further, the contact surface of the horizontal flange portion 4a and a horizontal flange portion 4b, the fault at the time of horizontal movement of the horizontal flange portion 4a and a horizontal flange portion 4b is left upper casing 43 and a right upper casing 44 when the upper casing opening to be described later Therefore, it is preferable to form with a low friction member.

  With regard to the steam turbine 1 according to the first embodiment having the above-described configuration, taking out of the internal compartment 3 by, for example, periodic inspection will be described with reference to FIGS.

First, the operation of the steam turbine is stopped, and processing such as draining the liquid inside is performed.
Thereafter, all the plurality of bolts 12 fixing the horizontal flange portion 4a and the horizontal flange portion 4b are removed. Further, the fixing means for fixing the upper left casing 43 and the upper right casing 44 is removed. When the fixing means is, for example, a flange and a bolt, all the bolts are removed.

Next, the upper left casing 43 and the upper right casing 44 are horizontally moved by pulling in the horizontal direction (H direction in FIG. 2) in a direction orthogonal to the axial direction of the rotor 2. When pulling, for example, a power machine capable of moving the upper left compartment 43 and the upper right compartment 44 such as a small crane is used. At this time, if the contact surface of the horizontal flange portion 4a and the horizontal flange portion 4b is formed of a low friction member as described above, the upper left compartment 43 and the upper right compartment 44 can be moved even if the power of the machine is small. It can be moved horizontally, saving labor.

The surface in the horizontal movement destination of the left upper casing 43 and a right upper casing 44 may be provided a moving surface 9 made of a low friction material, provided such rails in place of or moving surface 9 together with the moving surface 9 You can also. As a result, the upper left compartment 43 and the upper right compartment 44 move smoothly horizontally.

FIG. 7 is a schematic front view of the upper compartment and its surroundings after the upper compartment is horizontally moved.
By horizontally moving the upper left compartment 43 and the upper right compartment 44, a space 50 is formed between the upper left compartment 43 and the upper right compartment 44 as shown in FIG.
Note that the upper casing 4 1 before the movement of the left upper casing 43 and a right upper casing 44, the distance between the obstacle 20 present in the movement direction (a shown in FIG. 2), the upper casing 4 1 It is preferable that the length of the inner casing 3 is not less than half of the length in the direction perpendicular to the rotor axial direction. Can be taken out.

  After the left upper casing 43 and the upper right casing 44 are horizontally moved, the inner casing 3 is lifted by a small crane or the like, and is suspended beyond the upper left casing 43 or the upper right casing 44 to the outside. The inner casing 3 is suspended so as to exceed the upper portion of the recess 45 formed in the upper left casing 43 or the upper right casing 44. Thereby, when hanging up the internal compartment 3, the height which lifts the internal compartment 3 can be restrained low.

According to this embodiment, since it is possible to remove the upper compartment from the lower compartment without lifting the upper compartment, it is only necessary to secure a height sufficient to suspend the internal compartment, and the turbine is installed. The ceiling height of the building can be kept low.
In addition, when the existing equipment is remodeled to the form of the present embodiment, it is not necessary to use a large crane that has been used to lift the external casing. Therefore, the division of the turbine that could not be performed in parallel and the work using other large cranes can be performed in parallel, which shortens the process in the case of periodic inspection of the entire plant including the turbine. It becomes possible.

  First, as for the outline of the structure of the steam turbine in the second embodiment, the structure of the upper casing is different as will be described later, but the other parts are the same as those in the first embodiment. To do. The same reference numerals as those in the first embodiment represent the same items.

A structure of the upper compartment according to the second embodiment will be described with reference to FIGS. 8 and 9.
FIG. 8 is a schematic front view of the upper casing of the steam turbine according to the second embodiment and its surroundings. FIG. 9 is a perspective view of the upper compartment according to the second embodiment.

As shown in FIG. 9, the upper compartment 41 is formed in a substantially bowl shape by two end plates 41a and one side plate 41b.
Furthermore, the upper casing 41 is configured to be divided into two in the horizontal direction orthogonal to the axial direction of the rotor 2. That is, the upper compartment 41 is configured by assembling the upper left compartment 43 and the upper right compartment 44 fixed by fixing means (not shown). The fixing means only needs to be fixed so that the upper left casing 43 and the upper right casing 44 are not divided when the steam turbine 1 is not required to be divided, for example, when the steam turbine 1 is operated. A bolt or the like can be used.

The end plate 41a is formed by a member 41e in which a part of the lower portion near the center in the direction orthogonal to the rotor 2 is removable, and the member 41e is attached to the main body of the end plate 41a using a flange and a bolt. ing.

  Moreover, the upper compartment 41 is couple | bonded using the lower compartment and the horizontal flange parts 4a and 4b as above-mentioned. Further, the upper left compartment 43 constituting the upper compartment 41 is pivotally supported so as to be rotatable about a rotation center 46 which is in the same direction as the axial direction of the rotor 2 and supported by the lower compartment 42. Yes. Similarly, the upper right casing 44 that constitutes the upper casing 41 is axially supported so as to be rotatable about a rotation center 47 that is in the same direction as the axial direction of the rotor shaft and is supported by the lower casing 42. Yes. The rotation centers 46 and 47 can be formed by using, for example, a hinge.

  With respect to the steam turbine 1 according to the second embodiment having the above-described configuration, for example, taking out the internal compartment 3 by periodic inspection or the like will be described.

First, the operation of the steam turbine is stopped, and processing such as draining the liquid inside is performed.
Thereafter, all the plurality of bolts 12 fixing the horizontal flange portion 4a and the horizontal flange portion 4b are removed. Further, the fixing means for fixing the upper left casing 43 and the upper right casing 44 is removed.
Next, the member 41e is removed from the end plate 41a.

Then, the left upper casing 43 and a right upper casing 44, is moved by pulling in the (R direction in FIG. 8), respectively rotating in mind 4 6, the direction to rotate 47 around the. When pulling, for example, a power machine capable of moving the upper left compartment 43 and the upper right compartment 44 such as a small crane is used.

The left upper casing 43 and the upper right casing 44 after the movement are indicated by broken lines in FIG.
After the upper left casing 43 and the upper right casing 44 move, a space is formed above the lower casing 42.
In addition, as shown by 60 in FIG. 8, it is necessary to provide support rods 60 that respectively support the upper left casing 43 and the upper right casing 44 after movement.

  After the upper left casing 43 and the upper right casing 44 are rotated, the inner casing 3 is lifted by a small crane or the like, and is suspended beyond the upper left casing 43 or the upper right casing 44 to the outside. The inner casing 3 is suspended so as to move in the axial direction of the rotor 2 over the notch 43a or 44a formed by removing the member 41e. Thereby, when hanging up the internal compartment 3, the height which lifts the internal compartment 3 can be restrained low.

According to the present embodiment, as in the first embodiment, it is possible to remove the upper compartment from the lower compartment without lifting the upper compartment, so that the height enough to hang the internal compartment is secured. The ceiling height of the building where the turbine is installed can be kept low.
In addition, when the existing equipment is remodeled to the form of the present embodiment, it is not necessary to use a large crane that has been used to lift the external casing. Therefore, the division of the turbine that could not be performed in parallel and the work using other large cranes can be performed in parallel, which shortens the process in the case of periodic inspection of the entire plant including the turbine. It becomes possible.

  In the casing structure of the steam turbine configured so that the outer casing can be divided vertically into the upper casing and the lower casing, the upper casing is separated from the lower casing and removed without lifting the upper casing. It can be used as a casing structure of a turbine that has been made possible. Further, in the turbine casing structure of the turbine, it can be used as a method of taking out a member existing inside the outer casing from a gap formed by removing the upper casing of the outer casing.

DESCRIPTION OF SYMBOLS 1 Turbine 2 Rotor 3 Internal compartment 4 External compartment 11a Groove 11b Protrusion part 41 Upper compartment 42 Lower compartment 43 Upper left compartment (member which divided the upper compartment into two)
44 Upper right compartment (the upper compartment divided into two parts)
45 Indentation (small diameter position)

Claims (7)

A turbine configured to have an internal compartment in which a rotor is inserted and an external compartment provided outside the internal compartment, and to divide the external compartment up and down into an upper compartment and a lower compartment In the cabin structure of
The upper casing is configured to be split in two in the vertical direction,
Provided with a guide part for restricting each member divided into two parts of the upper casing to slide in a direction perpendicular to the axial direction of the rotor ,
The upper compartment is
The cross section in the direction perpendicular to the axis of the rotor is formed in a substantially semicircular shape,
The diameter around the rotor has a small diameter position and a large diameter position different from each other,
The turbine casing structure , wherein the small diameter position includes an axial position of the rotor in which the inner casing or the rotor is present . Providing flange portions facing each other in each of the upper casing and the lower casing,
The guide portion is
It is comprised from the groove | channel of the direction orthogonal to the axial direction of the said rotor provided in the opposing surface of one said flange part, and the projection part fitted to the said groove | channel provided in the opposing surface of the other said flange part. casing structure of claim 1 Symbol placement of the turbine and. It has an internal compartment in which a rotor is inserted, and an external compartment provided outside the internal compartment, and the external compartment is configured to be vertically divided into an upper compartment and a lower compartment. In the turbine casing structure,
The upper casing is configured to be split in two in the vertical direction,
Each member obtained by dividing the upper casing into two parts is axially supported so as to be rotatable about a rotation center supported in the lower casing in the same direction as the axial direction of the rotor. The turbine casing structure. The upper compartment is
It is formed from two semicircular end plates arranged facing the axial direction of the rotor, and a side plate provided between the end plates,
The turbine casing structure according to claim 3 , wherein the end plate is configured to be able to remove a part of a lower portion near a center in a direction orthogonal to the axial direction of the rotor. It has an internal compartment in which a rotor is inserted and an external compartment provided outside the internal compartment, and the external compartment is configured to be vertically divided into an upper compartment and a lower compartment, A guide portion is provided for restricting each member that divides the upper casing into two in a direction orthogonal to the axial direction of the rotor, and the upper casing has a cross section in the axis orthogonal direction of the rotor. A method of taking out an internal member of a turbine casing, which is formed in a substantially semicircular shape and has a small-diameter position and a large-diameter position, each having a different diameter around the rotor ,
After dividing the upper compartment and the lower compartment, the upper compartment is divided into two in the vertical direction,
The upper casing is divided into two parts, the sliding direction is regulated by the guide portion, and the sliding movement is performed in the direction perpendicular to the axis of the rotor.
A method for taking out an internal member of a turbine casing , wherein the member in the outer casing is taken out from a space formed by the sliding movement by being suspended beyond the upper portion of the small diameter position . A turbine configured to have an internal compartment in which a rotor is inserted and an external compartment provided outside the internal compartment, and to divide the external compartment up and down into an upper compartment and a lower compartment An internal member removal method for a vehicle compartment,
After dividing the upper compartment and the lower compartment, the upper compartment is divided into two in the vertical direction,
Each member divided into two parts of the upper casing is rotated around the rotation center that is the same as the axial direction of the rotor and supported by the lower casing,
A method for removing an internal member of a turbine casing, wherein the member inside the outer casing is extracted from a space formed by the rotation. After removing a part of the lower part near the center in the direction orthogonal to the axial direction of the rotor of each of the two end plates that are provided so as to face the axial direction of the rotor and constitute the external casing, 7. The method for removing an internal member of a turbine casing according to claim 6, wherein each member obtained by dividing the upper casing into two parts is rotated.

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